The present invention relates to a fully automatic method and apparatus for cutting products composed of a plurality of basic elements (items of clothing, shoes, sofa upholstery, etcetera) which are fully or partially made of a material which can be laid on a moving surface and can be cut continuously without any external manual intervention on a conveyor which is moving continuously and at a variable speed. Machines that cut the fabric in a layer set and in single layers are currently known in the specific field of the cutting of items of clothing. These two methods, which are the current state of the art, require a layout study which cannot be performed on the actual fabric being acquired; accordingly, they do not take into account the characteristics of the fabric, such as stripes, checked patterns, flowers etcetera or flaws found during the actual cutting of the fabric.
Also in the specific case of single-layer cutting, the fabric is cut in xe2x80x9cwindowsxe2x80x9d, where each window corresponds to a layout determined beforehand by optimization systems without taking into account the actual characteristics of the fabric that will be cut. In all these systems, the cutting logic system is practically the same, except for the fact that in the case of a layer set, a plurality of layers are cut simultaneously, while in the case of the single layer, the layering system is removed, eliminating this step but maintaining the entire logic system of the production system both upstream and downstream.
Examples of cutting systems are available from the documents U.S. Pat. No. 5,258,917, U.S. Pat. No. 4,419,820 and U.S. Pat. No. 5,172,326.
However, all such systems are operating sequentially, and need stoppings and human intervention.
The aim of the present invention is to revolutionize and fully automate, in all its parts, the laying, cutting and the cut part removal system for items of clothing and for products made entirely or partially of a material which can be laid on a moving surface to be cut, by providing a method and an apparatus which allow to cut any number of products, particularly items of clothing, continuously and automatically, attempting to minimize and ultimately eliminate all manual interventions.
This aim and other objects which will be described hereinafter are achieved by a method for automatically cutting in a continuous, real-time controlled operation, a material that can be laid over a continuously movable transport surface, the method comprising, in operational sequence, the steps of:
a) accommodating, in an automatic material magazine, materials to be cut in a predefined sequence;
b) removing from the material magazine and sending to a deposition system for subsequent deposition onto a continuously-moving transport surface, the material to be cut;
c) automatically depositing the material to be cut, so as to lay out in a layer on the transport surface which is moving continuously and at a variable speed;
d) acquiring all the geometric characteristics and defectiveness characteristics of a material surface to be cut and storing all said geometric and defectiveness characteristics in an electronic memory so as to be available for automatic, in real time, retrieval and processing;
e) optimizing the layout of shapes to be cut onto the material surface acquired in the previous step, in a fully automatic manner, by taking simultaneously into account all said geometric and defectiveness characteristics of the acquired material surface and outline characteristics regarding single product shapes and elementary piece shapes of complex products to be cut;
f) cutting said material laying out on said transport surface while moving continuously and at a variable speed therewith, the transport surface speed being adjustable so that the cutting step is started upon ending of the previous optimizing step;
g) removing from said continuously-moving transport surface the shapes cut during the previous step, and selectively depositing, either individually the single product shapes or, in respective packs, the elementary piece shapes for constituting a complex product; and
h) continuously exchanging information concerning the correct operation of the entire production sequence (X1, X2, X3, X4) between a computerized control system (SLAVE) and an automatic production control and data management system (MAIN), and on the basis of said information controlling, in real time, the entire synchronization of the production operation.
The above-described method and the related apparatus entail considerable advantages in the cutting sequence and specifically allow the following improvements:
1) Manual or automatic layout and optimization of the pieces to be cut on screen on an ideal fabric is eliminated, since the layout is generated when the fabric is to be cut, taking exactly into account all the characteristics of the fabric, acquired by the sensing system, at cutting time.
2) All the checks for fabric flaws, which had to be conducted before placing the rolls in the store, are no longer required.
3) Production becomes highly flexible, since at any moment the system can decide to halt production, roll up the fabric being cut, automatically remove from the store a new fabric to be cut, lay and cut a number xe2x80x9cnxe2x80x9d of more urgent items, roll up the fabric of the urgent items, take up again the old fabric that was being cut and continue the temporarily halted production without any manual intervention. All this can be done without requiring any predefined layout and in real time, under the supervision of a management program (MAIN+SLAVE).
4) Fabric waste can be optimized better than in the current state of the art. When a fault is detected during fabric laying, current technology in fact allows to obviate this problem as shown in FIG. 1. The fabric is moved back and laying resumes from the last complete shape affected by the flaw. In this manner, however, extra item pieces are obtained which are unusable and therefore a portion of fabric is wasted over its entire width. With the present invention, instead, since the shapes are arranged on the fabric acquired by the fabric sensing system, the exact location of the flaws is known and it is therefore possible to arrange the shapes in the best possible manner, avoiding said flaw as shown in FIG. 2, achieving a better result in terms of waste caused by fabric flaws.
5) The system for automatically removing the pieces allows to supply production sequences according to conventional production methods, i.e., a production line, or to supply production islands, where items are produced at a single station in a fully automatic manner depending on the required production.